Electric switch.



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ELECTRIC SWITCH.

APYLIGATIOH FILED DBO. 17, was.

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INVENTOR ATTORNEY- WITNCEaSES .rinirnn snares earner oasis GEORGE IB. THOMAS, OF BBIDGEPORT, CONNECTICUT, ASSIGNOB TO THE PERKINS ELECTRIC SWITCH MANUFACTURING COMPANY, OF BRIDGEPORT, CONNECTICUT,

A CORPORATION OF CONNECTICUT.

ELECTRIC SWITCH.

errata.

To all whom it may concern: 4

Be it known that I, GEORGE B. THOMAS, a citizen of the United States of America, and residing in the city of Bridgeport, in the county of F airfield and State of Connecticut, have invented certain new and useful Improvements in Electric Switches, of which the following is a specification.

My invention relates to electric switches and particularly to the spindle for carrying the contact piece, the object of my invention being to provide a spindle having the end which carries the operating handle or key effectively insulated from the end carrying the contact piece or coming into contact with electrically live parts of the switch mechanism.

In the accompanying drawings in which my invention is shown applied to a spindle for an incandescent lamp socket, Figure 1 is a side elevation of the switch spindle and key; Fig. 2 is a broken elevation of the key end on a larger scale; and Fig. 3 is a perspective of the spindle with the parts detached and in position for assembly.

The device commonly employed for insulating the operating key for the switch spindle is to thread or force upon the round spindle a metal bushing lined with insulation and thread the key upon the bushing. This is a very unsatisfactory method however since the heat of the lamp is often sutficient to so soften the insulation that the bushing merely swivels upon the spindle when the key is turned, and the switch mechanism is thus rendered inoperative.

The present invention provides an improved means for insulating the key A from the spindle and comprises a metallic shell 5 of angular shape, carrying a threaded stem 6 on which the key may be screwed. This stem may be made separate from the shell as shown in Fig. 3 and provided with a head 7 of angular contour col-forming to that of the shell and adapted to fit within the latter, the stem passing through a perforation therein.

An insulating washer 8 preferably of vul- Specification of Letters Patent.

Patented Sept. 2'3, rare.

Application filed December 17, 190B.- Serial No. 468,041.

canized fiber or other insulating material which will not soften under the heat of the socket, separates the stem from the angular end of the switch spindle 9, the latter being preferably spread to form a head 10 of angular outline. A washer 11 preferably of the same material shaped externally to fit the shell and internally to [it the angular end 10 of the switch spindle not-only insulates the latter from the sides of the shell 5 but centers it with relation to the key stem 6. A third washer l2is'fittedabove the head 10 and within the shell, and the whole is then rigidly united by rolling over the edges of the shell under pressure.

It will be readily seen that by this c0nstruction, the danger of the key stem swiveling upon the switch spindle, is reduced to a minimum since an insulating medium may be employed which is not affected by the heat to which it is likely to be subjected. Furthermore owing to the angular outline of the shell with which the key stem is rigid, on the one hand, and the angular head of the switch spindle on the other, there is a bite between the parts even though a softening insulation material be employed, and this is heightened by the unifying pressure exerted by the rolled over edges of the shell.

It is obvious that the precise construction illustrated may be de arted from without evading the scope of tie invention and that the device may be applied to switch spindles other than for sockets and I do not-limit myself to the precise structure shown.

I claim as my invention:

A spindle for switch mechanism comprising a spindle with angled head on one end, an angled shell surrounding said head and perforated in line with said spindle, a threaded key stem projecting through said perforation and provided with an angled head fitting within said shell, an insulating washer separating said key stem from the threadedover the switch spindle and jux- I name to this specification, in the presence scribed.

taposed to the 11head thereofi, the edges of of two subscribing Witnesses. said angled she being rolle over upon the last mentioned washer and serving to 100k GEORGE THOMAS 5 said parts together, substantially as de- Witnesses:

- G. V7. GOODRIDGE, In testimony whereof I have signed my H. W. GOLDSBOROUGH. 

